Circuit switching systems are well known in the art. Such circuit switching systems typically include multiple source modules that receive a signal and route the signal to one of multiple destination modules. Since an intended destination of a signal may vary with each signal received, the circuit switching systems typically include a centralized circuit switch that is interposed between all source modules and all destination modules. For each signal received by a source module, the centralized circuit switch establishes a temporary circuit connecting the source module and a destination module. The source module and destination module are then able to exchange signals via the established circuit. When the communication between the source module and the destination module ends, the centralized circuit switch tears down the established circuit.
For example, FIG. 1 is a block diagram of an exemplary circuit switching system 100 of the prior art. Circuit switching system 100 includes multiple source modules 101-103 and multiple destination modules 131-133. A centralized circuit switch 106 is coupled to each of the multiple source modules 101-103 via respective data links 111-113 and is further coupled to multiple destination modules 131-133 via respective data links 121-123. When a source module, such as source module 102, receives a signal that is intended for a destination module, such as destination module 133, switch controller 104 causes centralized circuit switch 106 to establish a temporary circuit 108 between source module 102 and destination module 133. Source module 102 and destination module 133 are then able to exchange signals via a circuit comprising link 112, circuit 108, and link 123. After the signal has been conveyed to destination module 133, switch controller 104 causes centralized switch 106 to tear down circuit 108.
A problem with a circuit switching system such as circuit switching system 100 is that centralized circuit switch 106 is a single fault zone upon which all interconnect depends. When centralized circuit switch 106 is disabled, the entire switching system 100 is disabled. In order to alleviate such a problem, some circuit switching systems implement redundant circuit switches that back up the centralized circuit switch 106, or sub-divide the centralized circuit switch 106 into multiple centralized circuit switches that each provide centralized circuit switching functionality to one of multiple switching zones. As a result, when one switch goes down the other switching zones will not be affected, and a redundant switch may assume the functions of the disabled switch. However, redundancy is expensive to implement. Furthermore, an increasingly complex centralized switching arrangement requires an increasingly complex centralized process to manage all connections through the centralized switching arrangement.
Therefore, a need exists for a method and an apparatus for providing circuit switching functionality without a need for a centralized circuit switch.